Doctors used to encourage cancer patients to conduct their lives in whatever way they choose while undergoing treatment — those who want to work and push themselves hard could continue to do so, while those who felt the desire or need to retreat from the stresses of everyday life were encouraged to do that as well. However, research suggests that when cancer patients experience extreme emotional or physical stress, even from vigorous exercise, their treatment may be less effective. While a healthy person may reap all sorts of physical and psychological benefits from a brisk run or a demanding class at the gym, this new study suggests that it may be better to take it easy before and after radiation or chemotherapy.

Stress Deactivates Cancer Treatments

In a laboratory at The Ohio State University in Columbus, associate professor of cardiovascular medicine Govindasamy Ilangovan, PhD, and his team examined the impact of stress on breast cancer cells subjected to radiation or chemotherapy. Where cancer therapy normally damages DNA in cancer cells and kills them, the researchers found that intense physical or psychological stress interrupts this process. The stress ends up creating “distress,” which induces production of a protein known as heat shock factor-1 (HSF-1). This, in turn, sparks a series of events — specifically elevating levels of the stress-sensitive protein Hsp27 — that allows cancer cells to survive by inhibiting apoptosis (cancer cell death). As a result, the tumor continues to grow unchecked.

In his experiments, Dr. Ilangovan found that…

  • When investigators induced heat shock factor-1 and Hsp27 into breast cancer cell cultures undergoing radiation, fewer cells were killed than when those proteins are not present.
  • When they treated cancer cells with the chemotherapy drug doxorubicin, the stress-related proteins likewise reduced the effectiveness of the drug.
  • When scientists introduced a molecule known to inactivate those stress proteins (the “siRNA” molecule), the destruction of cancer cells was restored in both cases.

These conclusions were published on-line in the September 2010 issue of the journal Molecular Cancer Research. The investigators expect that this mechanism will hold true for people (not just for laboratory cell samples) and also that the results will likely apply to other cancers as well — specifically to additional cancers that originate in glandular organs, including the lungs, breasts, colon, prostate, pancreas, stomach and cervix. Further research will explore this effect in the real world.

Take It Easy?

While the siRNA molecule itself isn’t a treatment option outside the laboratory, Dr. Ilangovan and his colleagues are trying to develop a drug that has the same effect. In the meantime, they recommend that cancer patients should take care to avoid physical and emotional stress during cancer treatment. Specifically, they suggest that cancer patients should …

  • Avoid excessive stress for at least two days before chemo or radiation. According to Dr. Ilangovan, the process of HSF-1 activation takes 48 hours, so engaging in an intense workout or emotionally taxing experience two days before therapy has the potential to reduce its effectiveness.
  • Take it easy physically and mentally for up to a week following cancer treatment, as well. This may be not a luxury but a vitally important precaution — researchers found that the impact of stress and the proteins it generates is even greater post-treatment.

Dr. Ilangovan told me that cancer patients shouldn’t stop exercising entirely before and after treatment, but rather should just keep exercise sessions light — for instance, engaging in gentle activities, such as yoga stretches or a relaxing swim. It’s also wise to do all you can to reduce emotional strain, which is frankly inevitable during cancer therapy. Some people prefer formal stress reducers, such as meditation or deep breathing, while others find relief simply through playing with grandchildren or playing cards. Choose whatever works best for you, and allow your body the time and space it needs to heal, physically and psychologically.